Properties of the Number 18931

Eighteen Thousand Nine Hundred Thirty-One

Basics

Value: 18930 → 18931 → 18932

Parity: odd

Prime: No

Previous Prime: 18919

Next Prime: 18947

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 11 × 1721

Divisors: 1, 11, 1721, 18931

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 100100111110011

Octal: 44763

Duodecimal: AB57

Hexadecimal: 49f3

Square: 358382761

Square Root: 137.58997056471813

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: No

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

T(n,k)=Number of (n+2)X(k+2) 0..2 arrays with every consecutive three elements in every row having 2 or 3 distinct values, in every column 1 or 2 distinct values, in every diagonal 2 distinct values, and in every antidiagonal 2 distinct values, and new values 0 upwards introduced in row major order. A252882

Fibonacci sequence beginning 3, 10. A22122

The point to which the powers of n merge on an 8-digit calculator. A216070

Solution of the complementary equation a(n) = 2·a(n-1) + b(n-1), where a(0) = 2, a(1) = 5, b(0) = 1, and (a(n)) and (b(n)) are increasing complementary sequences. A295057

Numbers n such that 121·2ⁿ-1 is a prime. A50586

Number of n X 2 arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 n X 2 array. A220147

Number of (n+2)X(1+2) 0..2 arrays with every consecutive three elements in every row having 2 or 3 distinct values, in every column 1 or 2 distinct values, in every diagonal 2 distinct values, and in every antidiagonal 2 distinct values, and new values 0 upwards introduced in row major order. A252877

Number of (3+2)X(n+2) 0..2 arrays with every consecutive three elements in every row having 2 or 3 distinct values, in every column 1 or 2 distinct values, in every diagonal 2 distinct values, and in every antidiagonal 2 distinct values, and new values 0 upwards introduced in row major order. A252885

a(1)=4, then least semiprime > a(n-1) such that when all in the sequence are concatenated together they form a prime. A85703

The number of permutations of n cards in which 2 is the first card hit and 3 the next hit after 2. A18931